incorporate review comments

Signed-off-by: Mayank Singh <mayankfz@gmail.com>

Author: mayankfz

CODEOWNERS

@@ -18,6 +18,13 @@
 /azurelinuxagent/common/rdma.py @longlimsft
 /azurelinuxagent/pa/rdma/ @longlimsft
 
+#
+# Azure Container Linux (ACL)
+#
+/azurelinuxagent/common/osutil/acl.py @mayankfz
+/config/acl/ @mayankfz
+/init/acl/ @mayankfz
+
 #
 # Linux Agent team
 #

azurelinuxagent/common/osutil/acl.py

@@ -0,0 +1,79 @@
+#
+# Copyright 2018 Microsoft Corporation
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+#
+# Requires Python 2.6+ and Openssl 1.0+
+#
+# Azure Container Linux (ACL) is an immutable, sysext-based distro derived
+# from Flatcar.  This osutil is a standalone copy of MarinerOSUtil with
+# ACL-specific overrides so that future Azure-Linux changes do not
+# inadvertently affect the immutable ACL image.
+#
+
+from azurelinuxagent.common.osutil.default import DefaultOSUtil
+
+
+class AclOSUtil(DefaultOSUtil):
+    def __init__(self):
+        super(AclOSUtil, self).__init__()
+        self.jit_enabled = True
+
+    @staticmethod
+    def get_systemd_unit_file_install_path():
+        # ACL delivers waagent as a sysext; /usr is read-only.
+        # Writable systemd units must go to /etc/systemd/system.
+        return "/etc/systemd/system"
+
+    @staticmethod
+    def get_agent_bin_path():
+        return "/usr/bin"
+
+    def is_dhcp_enabled(self):
+        return True
+
+    def start_network(self):
+        self._run_command_without_raising(["systemctl", "start", "systemd-networkd"], log_error=False)
+
+    def restart_if(self, ifname=None, retries=None, wait=None):
+        self._run_command_without_raising(["systemctl", "restart", "systemd-networkd"])
+
+    def restart_ssh_service(self):
+        # ACL uses sshd.socket for socket-activated SSH (similar to
+        # Flatcar/CoreOS).  Restarting sshd.service would conflict with
+        # the active sshd.socket.
+        pass
+
+    def stop_dhcp_service(self):
+        self._run_command_without_raising(["systemctl", "stop", "systemd-networkd"], log_error=False)
+
+    def start_dhcp_service(self):
+        self._run_command_without_raising(["systemctl", "start", "systemd-networkd"], log_error=False)
+
+    def start_agent_service(self):
+        self._run_command_without_raising(["systemctl", "start", "{0}".format(self.service_name)], log_error=False)
+
+    def stop_agent_service(self):
+        self._run_command_without_raising(["systemctl", "stop", "{0}".format(self.service_name)], log_error=False)
+
+    def register_agent_service(self):
+        self._run_command_without_raising(["systemctl", "enable", "{0}".format(self.service_name)], log_error=False)
+
+    def unregister_agent_service(self):
+        self._run_command_without_raising(["systemctl", "disable", "{0}".format(self.service_name)], log_error=False)
+
+    def get_dhcp_pid(self):
+        return self._get_dhcp_pid(["pidof", "systemd-networkd"])
+
+    def conf_sshd(self, disable_password):
+        pass

azurelinuxagent/common/osutil/factory.py

@@ -19,6 +19,7 @@
 import azurelinuxagent.common.logger as logger
 from azurelinuxagent.common.version import DISTRO_NAME, DISTRO_CODE_NAME, DISTRO_VERSION, DISTRO_FULL_NAME
 from azurelinuxagent.common.utils.distro_version import DistroVersion
+from .acl import AclOSUtil
 from .alpine import AlpineOSUtil
 from .arch import ArchUtil
 from .bigip import BigIpOSUtil
@@ -146,6 +147,9 @@ def _get_osutil(distro_name, distro_code_name, distro_version, distro_full_name)
     if distro_name == "iosxe":
         return IosxeOSUtil()
 
+    if "azure container linux" in distro_full_name.lower():
+        return AclOSUtil()
+
     if distro_name in ["mariner", "azurelinux"]:
         return MarinerOSUtil()
 

azurelinuxagent/common/osutil/mariner.py

@@ -17,14 +17,12 @@
 #
 
 from azurelinuxagent.common.osutil.default import DefaultOSUtil
-from azurelinuxagent.common.version import DISTRO_FULL_NAME
 
 
 class MarinerOSUtil(DefaultOSUtil):
     def __init__(self):
         super(MarinerOSUtil, self).__init__()
         self.jit_enabled = True
-        self.distro_full_name = DISTRO_FULL_NAME
 
     @staticmethod
     def get_systemd_unit_file_install_path():
@@ -44,10 +42,6 @@ def restart_if(self, ifname=None, retries=None, wait=None):
         self._run_command_without_raising(["systemctl", "restart", "systemd-networkd"])
 
     def restart_ssh_service(self):
-        # ACL uses sshd.socket for socket-activated SSH (similar to Flatcar/CoreOS).
-        # Restarting sshd.service would conflict with the active sshd.socket.
-        if "azure container linux" in self.distro_full_name.lower():
-            return
         self._run_command_without_raising(["systemctl", "restart", "sshd"])
 
     def stop_dhcp_service(self):

config/acl/waagent.conf

@@ -4,7 +4,8 @@
 
 Extensions.Enabled=y
 
-Provisioning.Agent=waagent
+# Auto-detect the provisioning agent (coreos-cloudinit or waagent).
+Provisioning.Agent=auto
 Provisioning.DeleteRootPassword=n
 Provisioning.RegenerateSshHostKeyPair=n
 Provisioning.SshHostKeyPairType=auto

init/acl/10-waagent-sysext.conf

@@ -1,2 +1,13 @@
+# Drop-in for multi-user.target on Azure Container Linux (ACL).
+#
+# WALinuxAgent is delivered as a systemd-sysext image.  Sysext units are
+# only visible after systemd-sysext.service merges the overlay, which
+# happens *after* the default target is already queued.  Without an
+# explicit "Upholds=", systemd has no dependency edge to pull
+# waagent.service into the boot transaction.
+#
+# "Upholds=" (systemd 249+) is a soft requirement: it starts the unit
+# whenever multi-user.target is active but does not fail the target if
+# waagent.service cannot start.
 [Unit]
 Upholds=waagent.service

setup.py

@@ -164,23 +164,24 @@ def get_data_files(name, version, fullname):  # pylint: disable=R0912
                        src=["config/clearlinux/waagent.conf"])
         set_systemd_files(data_files, dest=systemd_dir_path,
                           src=["init/clearlinux/waagent.service"])
+    elif name in ["mariner", "azurelinux"] and "azure container linux" in fullname.lower():
+        set_bin_files(data_files, dest=agent_bin_path)
+        set_logrotate_files(data_files)
+        set_conf_files(data_files, dest="/etc",
+                       src=["config/acl/waagent.conf"])
+        set_systemd_files(data_files, dest=systemd_dir_path,
+                          src=["init/acl/waagent.service"])
+        multi_user_target_drop_in_dir = os.path.join(systemd_dir_path, "multi-user.target.d")
+        set_systemd_files(data_files, dest=multi_user_target_drop_in_dir,
+                          src=["init/acl/10-waagent-sysext.conf"])
     elif name in ["mariner", "azurelinux"]:
         set_bin_files(data_files, dest=agent_bin_path)
         set_logrotate_files(data_files)
-        if "azure container linux" in fullname.lower():
-            set_conf_files(data_files, dest="/etc",
-                          src=["config/acl/waagent.conf"])
-            set_systemd_files(data_files, dest=systemd_dir_path,
-                                          src=["init/acl/waagent.service"])
-            multi_user_target_drop_in_dir = os.path.join(systemd_dir_path, "multi-user.target.d")
-            set_systemd_files(data_files, dest=multi_user_target_drop_in_dir,
-                              src=["init/acl/10-waagent-sysext.conf"])
-        else:
-            set_conf_files(data_files, dest="/etc",
-                        src=["config/mariner/waagent.conf"])
-            set_systemd_files(data_files, dest=systemd_dir_path,
-                            src=["init/mariner/waagent.service"])
-            set_udev_files(data_files)
+        set_conf_files(data_files, dest="/etc",
+                       src=["config/mariner/waagent.conf"])
+        set_systemd_files(data_files, dest=systemd_dir_path,
+                          src=["init/mariner/waagent.service"])
+        set_udev_files(data_files)
     elif name == 'ubuntu':
         set_conf_files(data_files, src=["config/ubuntu/waagent.conf"])
         set_logrotate_files(data_files)